That chain was specially developed for the application in the GM unified powerplant, I think it was developed by Gates especially to handle the power and remain durable. I'm not sure there was anything like it at the time, even in transfer cases. Thanks for showing this to me torn down I've always wondered what it looked like inside
Really , their are many full spools on the roads and that is the same as a welded up diff, you need to re-learn how to drive , if you grew up driving go karts with solid axels or any race car , they all have locked or no diff , FI cars are locked solid axel and they go around corners better than any car !
The chain was engineered and developed for the front drive Olds Toronado by Morse Chain Co Inc. It proved so strong and durable that the unit / chain was used in the GMC Motor Homes with no modification.
It hooked hard when the front wheels came up from what we were told. Might help straighten it on wheel stands welding it up. Even pull to both rear tires.
12-12-2019.Hello there l,m the guy that holds the patent on that transmission.Long storie short get a plastic pool and put the moter inthe middle of it.Go slow .Were is the shop manule?Dont hirt my toy.Have fun and draw out your draem it helps,Bill.
OMG! Did I get it right? Did you design this transmission?! I mean ... I know it was a team of engineers ... but am I talking to one of them here????? :o
If it's off road weld it, I would not weld the gears together it will cause stress and and risk a differential failure. I've seen another way remove the open differential gears ( I'm guessing it's 2 small gears rather than 4 small gears) take the small gears out and weld up a couple tooth valleys, so that it keeps them from rotating make it snug so that there is no backlash which would also stress the gears. If you do not like the results of a solid lock up you just have to replace the 2 small gears that you welded on.
If you go with a fully locked differential, it will not turn well at all. It will start hopping. And the chance to break something. I don't know if anyone made an LSD for them. You'll be fine with an open diff. EDIT, saw the next video. If you're using it for a RWD application, then welding it will work, but you'll still get that hop when turning tight.
@@puffkendrick6850I know this post was 3 years ago , but any chance you still have one ? I'm building a project , plus I'm in Australia, but we can sort out freight if available , thanks
You can take the 455 and that transmission and cut the floor of the bed out of a S10 and its rearend, tank etc and put the olds 455 engine and transaxle in between the rear frame rails of the S10....When your done youve got a 455 cubic inch rear engine S10..for cheap
You didn’t happen to take the final drive off, did you? I’m trying to get one off right now and it’s not letting go. I’m wondering if there’s something on the inside I need to remove other than just the bolts to the tail housing.
My uncle used a 72 Toronado engine and drive train for a motor home he built out of wrecked airstream trailer. It has been sitting a long time and I am trying to transport it in a flatbed but can’t get it out of park. Any ideas?
I would expect it to fry both since you not dealing with a solid axle that plants the left rear and lifts the right rear due to reaction torque from the drive shaft
@@111000100101001 Yes, it will fry both with the open diff. I have this setup (Olds 455 + TH425) in the back seat my '70 VW sedan. There is no side-to-side torque reaction because the diff is directly bolted to the front of the gear case AND bolted solid to the engine block, which in turn is bolted to the frame. One solid lump with 2 half-shafts sticking out the sides. There IS a torque reaction but it is front-to-back. This setup lifts the front end and PLANTS the back end. Traction is not a problem at all!! Been driving this on the street for 6 years, I laugh every time I drive it.
Do you think this would be pretty much the same thing as a motor and th400 facing backwards bolted to a transfer case and then from the tranfercase to a irs differential that is mounted underneath the transmission? I'm working on building a poor man's sandrail but with v8 power and a transmission that's gonna last
I built a sand rail in 2000. It used a Turbo 425 with a Olds 215 Aluminum V8. My dad actually originally built the combination for a Crew Cab VW Transport. It worked in the buggy very well but the only way to re-gear it is to take the rear cover off and get rid of the belts, go to timing chain and gears and that is how you get gears that work with Paddles in the sand. I have 33" Paddles with 5.30 final drive now... other than its not the lightest, its stupid strong.
@@aaronlenz9964this makes no sense whatsoever. The words "belts and timing chain" have zero to do with a drive axle of any kind. If this is the method to "re-gearing" then we must be on Mars Edit : I'm thinking you are talking about some kind of cvt system...a snowmobile clutch so to speak.. but I dunno for sure what you are saying
He's not welding the gears to the axls , he's welding the spider gears to the ring gear of the diff , to make a welded locker , has been don't for years with good results and I believe this is a rear drive application
Well not much as a Jag V12 is a lot smaller motor than it was designed to take , in fact the 12 is almost half the size of a 500 ci caddy V8 that this was originally put behind !
Hey there hi there ho there, I am using a 307 tornado engine and front wheel drive transmission for a wheelchair accessible 1951 Chevy panel. The ring and pinion gears are approximately 320 and while that gives me great top end and it takes off okay it is so high that when we try to slow down in the mountains just using the engine compression she just revs right up and does not slow down. So where might I find different ring and pinion gears to lower this transmission gear ratio? Thanks
All the TH-425 is is basically a TH-400 4x4 transfer case without the rear output shaft. Also, FWD cars only have open differentials because there's no need for Positraction/limited-slip like on a RWD car.
No. Chevy has its own bellhousing bolt pattern. Unless someone makes an adapter. Cadillac or Oldsmobile engines were used behind these. Buick and Pontiac engines share the same bolt pattern but never seen any used with the THM 425.
One cannot just weld an open differential to make it a posi. I cringe when I hear this! Doing so defies physics !!!!!! As someone mention if you’re going perfectly straight then in theory it would work but any car that isn’t able to make a turn is essentially useless. That said on a turn or a curve in the road the out board wheel must cover a greater distance and as such it’s actually rotating at a faster speed then the inboard wheel. No imaging if diff were locked so that the outboard wheel couldn’t turn faster! There would be tremendous drag or stress on that component. Even posi differentials aren’t transferring power to both wheels on a curve, or at least not 100% like in a straight line. Just food for thought
And after reading the whole post you wrote I know you don't know anything about cars , have you ever heard of locker diffs like the Detroit Locker from Ford ???? Hmmmm, you say no posi transfered 100 percent to both wheels , best you do some research hay, the Ford Detroit Locker car diff , sold in many many cars and F100s or F250s locks both axles after one spins three quarters of a turn , 100 percent locked and 100 percent drive to both wheels , GM had a version so did Dana in Chrysler's ! There are Torsen diffs that do the same ! On road cars
For one I’m not talking about posi traction diffs or Detroit lockers. I’m talking about EXACTLY what I said that one cannot just weld both of the inners to make it positraction. And you proved you don’t know what you’re taking about even posi units do NOT give power to both wheels once the car is on a curve. The out board wheel must turn fast so how does that happen if they’re locked together turning at the same speed? I just love when people take things out of context. So being you know everything you’re saying I can take an open differential and just weld it so both sides get power and all will be fine? Is that correct? There’s an episode of watch JR go where they did exactly this and welded both sides together. Guess how long the rear end lasted? About 10-15 minutes after making afew turns and trying to do donuts. But that had nothing to do with welding it to make a non slip diff a “posi”
That chain was specially developed for the application in the GM unified powerplant, I think it was developed by Gates especially to handle the power and remain durable. I'm not sure there was anything like it at the time, even in transfer cases. Thanks for showing this to me torn down I've always wondered what it looked like inside
You weld up the diff, dont expect that car to go around corners the way it should.
😆😆
Yup. I’d definitely leave it open. It won’t steer for nothing locked.
@@ninjasupreme5966it's a rear drive application !
Really , their are many full spools on the roads and that is the same as a welded up diff, you need to re-learn how to drive , if you grew up driving go karts with solid axels or any race car , they all have locked or no diff , FI cars are locked solid axel and they go around corners better than any car !
The chain was engineered and developed for the front drive Olds Toronado by Morse Chain Co Inc. It proved so strong and durable that the unit / chain was used in the GMC Motor Homes with no modification.
It hooked hard when the front wheels came up from what we were told. Might help straighten it on wheel stands welding it up. Even pull to both rear tires.
That would be insane. I think that settles it. This thing needs to be posi!
12-12-2019.Hello there l,m the guy that holds the patent on that transmission.Long storie short get a plastic pool and put the moter inthe middle of it.Go slow .Were is the shop manule?Dont hirt my toy.Have fun and draw out your draem it helps,Bill.
OMG! Did I get it right? Did you design this transmission?! I mean ... I know it was a team of engineers ... but am I talking to one of them here????? :o
@@renatoigmed GM owns the patent, this guy has a patent on bullshit.
howdy bill, im 20 and i just bought a 69 toronado with one of these big fellas in the engine bay, any other tips for when i take everything apart?
Great video as usual. Being a Fun car and not a "Serious" one, i would weld it.
WELD IT! WELD IT! WELD IT! WELD IT! WELD IT!
I have a cadillac Eldorado when i shift the gear from park to drive the car not moving. Can u tell me what is the problem?
The GMC motorhome guys also have some other gear ratios for these, 3.70 for instance
I have that gear box but I don't know how to replace inside clutches
If it's off road weld it, I would not weld the gears together it will cause stress and and risk a differential failure. I've seen another way remove the open differential gears ( I'm guessing it's 2 small gears rather than 4 small gears) take the small gears out and weld up a couple tooth valleys, so that it keeps them from rotating make it snug so that there is no backlash which would also stress the gears. If you do not like the results of a solid lock up you just have to replace the 2 small gears that you welded on.
If you go with a fully locked differential, it will not turn well at all. It will start hopping. And the chance to break something. I don't know if anyone made an LSD for them. You'll be fine with an open diff.
EDIT, saw the next video. If you're using it for a RWD application, then welding it will work, but you'll still get that hop when turning tight.
I have 3 of these 425 setups looking for a new home
@@puffkendrick6850 price and location
@@puffkendrick6850I know this post was 3 years ago , but any chance you still have one ? I'm building a project , plus I'm in Australia, but we can sort out freight if available , thanks
Greetings from Russia, dude!
You can take the 455 and that transmission and cut the floor of the bed out of a S10 and its rearend, tank etc and put the olds 455 engine and transaxle in between the rear frame rails of the S10....When your done youve got a 455 cubic inch rear engine S10..for cheap
That's my kinda of project!
what is the canister atop the th425 next to the dipstick?
I build a clutch-type limited slip differential for the TH425 final drive.
You have any details on that? Sounds awesome!
You didn’t happen to take the final drive off, did you? I’m trying to get one off right now and it’s not letting go. I’m wondering if there’s something on the inside I need to remove other than just the bolts to the tail housing.
My uncle used a 72 Toronado engine and drive train for a motor home he built out of wrecked airstream trailer. It has been sitting a long time and I am trying to transport it in a flatbed but can’t get it out of park. Any ideas?
They make an LSD for the TH425 final drive, check out Applied GMC for a positraction for these
I’d keep it differential. I wonder if anyone ever tried to put something like this is a Jeep XJ. Mid engine.
I'd leave it open diff if you plan on keeping it or ever street driving it
I'm planning on only minimal street use. Is a welded diff really all that bad on the street?
@@dickysgarage7120 it doesnt sound good if you ask me, but if it won't be street driven regularly or much, go for it
@@beebeegun16 I'm going to do a little experiment to see how bad it will be.
Wow wow wow 😳
Do it!!!
Weld it or leave it alone? lol
I'm a few years late seeing your video, but could you put an air locker in it like they do in 4 wheel drives and not weld the differential?
Where did you weld the differential?? I want to put this set up in the back of my Hearse. But I don't want a one wheel wonder. How did it turn out?
I never welded it. I was afraid I'd mess up something I couldn't replace. With the planetary gears it actually burns both more often than not.
I would expect it to fry both since you not dealing with a solid axle that plants the left rear and lifts the right rear due to reaction torque from the drive shaft
@@dickysgarage7120 did you ever get anything better than the factory slip set up?
@@111000100101001 Yes, it will fry both with the open diff. I have this setup (Olds 455 + TH425) in the back seat my '70 VW sedan. There is no side-to-side torque reaction because the diff is directly bolted to the front of the gear case AND bolted solid to the engine block, which in turn is bolted to the frame. One solid lump with 2 half-shafts sticking out the sides.
There IS a torque reaction but it is front-to-back. This setup lifts the front end and PLANTS the back end. Traction is not a problem at all!!
Been driving this on the street for 6 years, I laugh every time I drive it.
Do you think this would be pretty much the same thing as a motor and th400 facing backwards bolted to a transfer case and then from the tranfercase to a irs differential that is mounted underneath the transmission? I'm working on building a poor man's sandrail but with v8 power and a transmission that's gonna last
I built a sand rail in 2000. It used a Turbo 425 with a Olds 215 Aluminum V8. My dad actually originally built the combination for a Crew Cab VW Transport. It worked in the buggy very well but the only way to re-gear it is to take the rear cover off and get rid of the belts, go to timing chain and gears and that is how you get gears that work with Paddles in the sand. I have 33" Paddles with 5.30 final drive now... other than its not the lightest, its stupid strong.
@@aaronlenz9964this makes no sense whatsoever.
The words "belts and timing chain" have zero to do with a drive axle of any kind. If this is the method to "re-gearing" then we must be on Mars
Edit : I'm thinking you are talking about some kind of cvt system...a snowmobile clutch so to speak.. but I dunno for sure what you are saying
You can't weld the diff gears to the axles. I would imagine you'd end up snapping the axles driving it during turns.
He's not welding the gears to the axls , he's welding the spider gears to the ring gear of the diff , to make a welded locker , has been don't for years with good results and I believe this is a rear drive application
Never seen one at the drag racing track.... Probably would have ripped that rubber chain but to shreds
It's a metal chain.
I wonder what would happen if someone put a jaguar v12 in front of a th425.
Well not much as a Jag V12 is a lot smaller motor than it was designed to take , in fact the 12 is almost half the size of a 500 ci caddy V8 that this was originally put behind !
There were plans to use a V12 engine in the 1967 Cadillac Eldorado, but it was scrapped because of cost.
Hey there hi there ho there, I am using a 307 tornado engine and front wheel drive transmission for a wheelchair accessible 1951 Chevy panel. The ring and pinion gears are approximately 320 and while that gives me great top end and it takes off okay it is so high that when we try to slow down in the mountains just using the engine compression she just revs right up and does not slow down. So where might I find different ring and pinion gears to lower this transmission gear ratio? Thanks
Add a jake brake!
an lsd kit might be the way if it even exists xD
Ребята на заводе действительно заморочились!
It’s front wheel drive. It’s gonna have a hard time turning. You can end up breaking an axle.
All the TH-425 is is basically a TH-400 4x4 transfer case without the rear output shaft. Also, FWD cars only have open differentials because there's no need for Positraction/limited-slip like on a RWD car.
You can buy a spool to lock it.. why not that instead of welding.. you can't go back after welding it.
can u ls swap a 85 oldsmobile tornado fwd with that trans
No. Chevy has its own bellhousing bolt pattern. Unless someone makes an adapter. Cadillac or Oldsmobile engines were used behind these. Buick and Pontiac engines share the same bolt pattern but never seen any used with the THM 425.
One cannot just weld an open differential to make it a posi. I cringe when I hear this! Doing so defies physics !!!!!! As someone mention if you’re going perfectly straight then in theory it would work but any car that isn’t able to make a turn is essentially useless. That said on a turn or a curve in the road the out board wheel must cover a greater distance and as such it’s actually rotating at a faster speed then the inboard wheel. No imaging if diff were locked so that the outboard wheel couldn’t turn faster! There would be tremendous drag or stress on that component. Even posi differentials aren’t transferring power to both wheels on a curve, or at least not 100% like in a straight line. Just food for thought
And after reading the whole post you wrote I know you don't know anything about cars , have you ever heard of locker diffs like the Detroit Locker from Ford ???? Hmmmm, you say no posi transfered 100 percent to both wheels , best you do some research hay, the Ford Detroit Locker car diff , sold in many many cars and F100s or F250s locks both axles after one spins three quarters of a turn , 100 percent locked and 100 percent drive to both wheels , GM had a version so did Dana in Chrysler's ! There are Torsen diffs that do the same ! On road cars
For one I’m not talking about posi traction diffs or Detroit lockers. I’m talking about EXACTLY what I said that one cannot just weld both of the inners to make it positraction. And you proved you don’t know what you’re taking about even posi units do NOT give power to both wheels once the car is on a curve. The out board wheel must turn fast so how does that happen if they’re locked together turning at the same speed? I just love when people take things out of context. So being you know everything you’re saying I can take an open differential and just weld it so both sides get power and all will be fine? Is that correct? There’s an episode of watch JR go where they did exactly this and welded both sides together. Guess how long the rear end lasted? About 10-15 minutes after making afew turns and trying to do donuts. But that had nothing to do with welding it to make a non slip diff a “posi”
How about doing it the right way? Not like walt Disney would do. Why micky mouse it ? Just get good parts and make it right.